• Title/Summary/Keyword: smoke detection

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An Experimental Study on the Comparison of Operating Temperatures in Thermal Detector due to Tunnel Fire (터널 화재 시 열감지기 작동 온도의 비교에 관한 실험적 연구)

  • Roh, Hyeong-Ki;Park, Kwang-Young;Im, Seok-Been
    • Journal of the Korean Society of Hazard Mitigation
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    • v.11 no.1
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    • pp.23-27
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    • 2011
  • Due to the rapid development of construction technology with effective land utilization in this nation, many tunnels were and are being built across the country. However, the smoke and the heat generated from tunnel fire are the most important critical factors which may results in both massive personal injury and property damage, especially, due to the closed surrounding of the tunnel. Considering this particular nature of the tunnels, this study aims to install a fire detection system using an optic fiber cable to measure the temperature changes, compare, and analyze the resulted values with the times of temperature changes of the sensor by performing fire simulations under the same condition as a real fire test. From the results, it has been found that the temperature sensor detects a fire occurrence and generates an alarm within one minute after ignition for both a real fire test and a fire simulation alike, and also that the characteristics of temperature changes of the sensor has close relations with the speeds of the currents inside the tunnel. In addition, considering the tunnel fires can affect the evacuation efficiency and the fire extinguishing activities of the fire brigade inside the tunnel, the temperature sensor must be able to search and find the locations and directions of the fires correctly.

Design and Verification of Addressable Automatic Fire Detection System for Existing Apartments (기존아파트의 적용성을 고려한 주소형 자동화재탐지설비의 설계 및 검증)

  • An, Hyunsung
    • Land and Housing Review
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    • v.13 no.4
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    • pp.105-114
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    • 2022
  • Non-fire activated fire alarms caused by such actions as cigarette smoke, cooking, and high humidity are fire safety risk factors. In such instances, it is important to quickly locate and replace the actuated detector. However, it is difficult to locate those detectors because most do not have an address function. While new apartments can incorporate addressable fire alarm detectors, in existing apartments there are limitations in converting over to addressable detectors due to cost and power line issues. This study developed an efficient address function for fire alarms in existing apartments. The newly developed system consists of the existing receiver, and a proposed addressable repeater and detector. Utilizing an experimental setup, the performance of the proposed address monitoring system was confirmed to be stable and compatible with the receiver and existing detectors.

Characteristics of Fire-induced Thermal-Flowfields in an Underground Utility Tunnel with Ventilation (화재 발생시 환기방식에 따른 지하공동구내 열유동 특성 연구)

  • Kim, Hong-Sik;Hwang, In-Ju;Kim, Yun-Je
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.1845-1850
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    • 2003
  • The underground utility tunnels are important facility as a mainstay of country because of communication developments. The communication and electrical duct banks as well as various utility lines for urban life are installed in the underground utility tunnel systems. If a fire breaks out in this life-line tunnel, the function of the city will be discontinued and the huge damages are occurred. In order to improve the safety of life-line tunnel systems and the fire detection, the behaviors of the fire-induced smoke flow and temperature distribution are investigated. In this study we assumed that the fire is occurred at the contact or connection points of cable. Numerical calculations are carried out using different velocity of ventilation in utility tunnel. The fire source is modeled as a volumetric heat source. Three-dimensional flow and thermal characteristics in the underground tunnel are solved by means of FVM (Finite Volume Method) using SIMPLE algorithm and standard ${\kappa}-{\varepsilon}$ model for Reynolds stress terms. The numerical results of the fire-induced flow characteristics in an underground utility tunnel with different velocity of ventilation are graphically prepared and discussed.

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A Numerical Modeling of Smoke Behavior and Detection in a Pressurized Module(PM) of the International Space Station(ISS) (국제우주정거장의 가압모듈에서 연기거동 및 감지에 관한 수치 모델링)

  • Park, Seul-Hyun;Lee, Joo-Hee;Kim, Youn-Kyu;Hwang, Cheol-Hong
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2011.11a
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    • pp.7-10
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    • 2011
  • 최근 국제우주정거장에서 화재안전에 관한 중요성의 인식으로 화재의 감지/소화의 메커니즘을 구체적으로 이해하기 위한 다양한 연구들이 시도되고 있다. 본 연구에서는 국제우주정거장에서 각종 실험과 연구를 진행하는 가압모듈을 대상으로 환기, 연기거동 및 감지에 관한 수치모델링을 수행하였다. 수치모델링은 NIST에서 개발된 FDS (Fire Dynamic Simulator)가 사용되었다. 국제우주정거장 내부는 마이크로중력환경으로 부력이 존재하지 않아 화재 발생 시 화염 및 연기거동은 지상에서의 현상들과 큰 차이를 보이게 된다. 따라서 현재 가압모듈에서 적용되고 있는 환기조건의 변화에 따른 연기거동 및 감지특성에 대한 연구는 향후 국내의 국제 우주정거장 실험 참여를 위한 기초적인 정보를 제공할 것으로 기대된다.

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Development of Complex USN Sensor for Zero Energy House with Blind System (블라인더가 설치된 제로에너지 하우스를 위한 복합 USN 센서 개발)

  • Kim, Kee-Hwan
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.4
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    • pp.221-227
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    • 2013
  • In this paper, zero-energy house in order to monitor the energy savings come with Zigbee communication temperature humidity, smoke detection, illumination and CO2 to develop complex sensor board a protocol for handling about it dealt. In particular, indoor space to mount the sensor based on the location of the control algorithm, so it varies through the Zigbee wireless sensor mounting position is free, and the advantage of being able to change. Also, the energy loss that occurs through the window can be reduced to the room lighting can play an important role in the control system.

Establishment of analytical methods for HPHC list of mainstream cigarette smoke (담배 주류연 중 7개 그룹의 유해성분(HPHC) 분석법 확립 및 유효성 평가)

  • Park, Hyoung-Joon;Lee, Jin-Hee;Cho, So-Hyun;Heo, Seok;Yoon, Chang-yong;Baek, Sun-Young
    • Analytical Science and Technology
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    • v.28 no.6
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    • pp.385-397
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    • 2015
  • Harmful and potentially harmful constituents (HPHCs) are chemical compounds in tobacco smoke that cause harm to smokers and non-smokers. This study established and validated methods for the analysis of HPHCs from mainstream cigarette smoke. The analyzed HPHCs were categorized into seven groups: aromatic amines, volatile organic compounds (VOCs), heavy metals, tobacco specific nitrosamines (TSNAs), benzo[a]pyrene (B[a]P), ammonia, and carbonyl compounds. The methods were validated by specificity, linearity, limit of detection (LOD), accuracy, precision, and recovery. These validated methods were then applied to the reference cigarettes (1R5F, 3R4F). The correlation coefficients (r2) for the calibration curves of the seven groups were over 0.995. The LODs showed values of 0.01-0.04 ng/cig cig for aromatic amines, 0.01-0.16 μg/cig for VOCs, 0.01-1.27 ng/cig for heavy metals, 0.06-0.28 ng/cig for TSNAs, 0.04 ng/cig for benzo[a]pyrene, 0.08 μg/cig for ammonia, and 0.78-1.77 μg/cig for carbonyl compounds. The precisions obtained from the intra and inter-day batches were less than 15%. The accuracy and the recovery range were less than 15% and 79.2-117.5%, respectively. The proposed methods can therefore be applied for determining HPHCs in tobacco mainstream smoke.

The Early Prognosis of Burn Patients with Elevated Initial Arterial Carboxyhemoglobin Level (초기 동맥혈 Carboxyhemoglobin 농도가 높았던 화상 환자들의 예후지표에 관한 연구)

  • Choi, Chang Soon;Kim, Cheal Hong;Kim, Keun Sook;Lee, Tae-Yu;Chung, Youn Son;Eom, Kwang Seok;Park, Young Bum;Jang, Seung Hun;Kim, Dong Gyu;Park, Myung Jae;Lee, Myung Goo;Hyun, In-Gyu;Jung, Ki-Suck;Kim, Jong Hyun
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.2
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    • pp.188-197
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    • 2003
  • Background : Smoke inhalation injury is an important determinant of mortality in burn patients. The early detection of inhalation injury in burn patients is important because the incidence of respiratory failure after inhalation injury was known to be high, with hypoxemia, pneumonia, and prolonged ventilatory support being commonplace. Acute carbon monoxide poisoning was one feature of smoke inhalation. The purpose of our study were to investigate the clinical characteristics of burn patients whose initial arterial carboxyhemoglobin (COHb) level had been elevated, to assess the clinical impact of COHb for smoke inhalation injury. Methods : Among 1,416 burn patients had been admitted at our institution from August 1, 2001 to July 31, 2002, 39 patients whose initial arterial COHb level have been more than 5% were included. We compared clinical scoring system for inhalation injury, percent total body surface area (%TBSA) burn, initial chest X-ray findings, APACHE II scores and SAPS II scores between survivors (n=27) and non-survivors (n=12) retrospectively. Results : COHb level were 9.7(5.71% and 10.3(8.81% in survivors and in non-survivors (p>0.05). Mean %TBSA burn of survivors and non-survivors were $16.6{\pm}17.8%$ and $60.7{\pm}28.8%$ (p<0.001). We did not find any difference in clinical scoring system, initial chest X-ray findings in survivors and in non-survivors. But %TBSA burn, APACHE II and SAPS II scores were high in non-survivors than in survivors significantly. Important factors associated with death were %TBSA burn, APACHE II scores, SAPS II scores, and the most important factor in predicting mortality was %TBSA burn. Conclusion : Burn patients with elevated initial arterial COHb level showed poor prognosis, but further study may be performed to know that the effect of COHb on prognosis in burn patients accompanying smoke inhalation.

Fire Detection using Deep Convolutional Neural Networks for Assisting People with Visual Impairments in an Emergency Situation (시각 장애인을 위한 영상 기반 심층 합성곱 신경망을 이용한 화재 감지기)

  • Kong, Borasy;Won, Insu;Kwon, Jangwoo
    • 재활복지
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    • v.21 no.3
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    • pp.129-146
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    • 2017
  • In an event of an emergency, such as fire in a building, visually impaired and blind people are prone to exposed to a level of danger that is greater than that of normal people, for they cannot be aware of it quickly. Current fire detection methods such as smoke detector is very slow and unreliable because it usually uses chemical sensor based technology to detect fire particles. But by using vision sensor instead, fire can be proven to be detected much faster as we show in our experiments. Previous studies have applied various image processing and machine learning techniques to detect fire, but they usually don't work very well because these techniques require hand-crafted features that do not generalize well to various scenarios. But with the help of recent advancement in the field of deep learning, this research can be conducted to help solve this problem by using deep learning-based object detector that can detect fire using images from security camera. Deep learning based approach can learn features automatically so they can usually generalize well to various scenes. In order to ensure maximum capacity, we applied the latest technologies in the field of computer vision such as YOLO detector in order to solve this task. Considering the trade-off between recall vs. complexity, we introduced two convolutional neural networks with slightly different model's complexity to detect fire at different recall rate. Both models can detect fire at 99% average precision, but one model has 76% recall at 30 FPS while another has 61% recall at 50 FPS. We also compare our model memory consumption with each other and show our models robustness by testing on various real-world scenarios.

Analysis on a Location Compatibility of Forest Fire Detection Facilities according to Classification of Forest Fire Hazard Regions Types in Samcheok Area (삼척지역 산불위험지 구분에 따른 감시시설의 위치 적합성에 관한 연구)

  • Lee, Si-Young;An, Sang-Hyun
    • Fire Science and Engineering
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    • v.22 no.3
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    • pp.265-271
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    • 2008
  • This study analyzed on the area of Samcheok, Kangwondo about forest fire alarming area and enlargement of the area. Then, visible area by unattended watching camera and watchtower for forest fire which were run by Samcheok was cross-checked with geographic information system, and it ould be whether effective on watching the area here the forest fire risk was high enough and also it could be expanded to larger forest fire. The result of study, the visible area by watching facilities only holds for 13.4% of the whole forest fire alarming area, but the forest fire can be observed even though it is occurred in small valley because of smoke and all the forest fire have been occurred in daytime. Therefore, it can be determined that watching area will be extended around 50.3% while the observation radii of watching facilities raise by 4km. However, Samcheok has much greater area of mountain area in compared to any other cities or counties, watching facilities should be installed and run additionally for extinguishing the forest fire from the beginning.

Design of Smart Device Assistive Emergency WayFinder Using Vision Based Emergency Exit Sign Detection

  • Lee, Minwoo;Mariappan, Vinayagam;Mfitumukiza, Joseph;Lee, Junghoon;Cho, Juphil;Cha, Jaesang
    • Journal of Satellite, Information and Communications
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    • v.12 no.1
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    • pp.101-106
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    • 2017
  • In this paper, we present Emergency exit signs are installed to provide escape routes or ways in buildings like shopping malls, hospitals, industry, and government complex, etc. and various other places for safety purpose to aid people to escape easily during emergency situations. In case of an emergency situation like smoke, fire, bad lightings and crowded stamped condition at emergency situations, it's difficult for people to recognize the emergency exit signs and emergency doors to exit from the emergency building areas. This paper propose an automatic emergency exit sing recognition to find exit direction using a smart device. The proposed approach aims to develop an computer vision based smart phone application to detect emergency exit signs using the smart device camera and guide the direction to escape in the visible and audible output format. In this research, a CAMShift object tracking approach is used to detect the emergency exit sign and the direction information extracted using template matching method. The direction information of the exit sign is stored in a text format and then using text-to-speech the text synthesized to audible acoustic signal. The synthesized acoustic signal render on smart device speaker as an escape guide information to the user. This research result is analyzed and concluded from the views of visual elements selecting, EXIT appearance design and EXIT's placement in the building, which is very valuable and can be commonly referred in wayfinder system.